Feeder for a tube-filling machine

ABSTRACT

The present invention relates to feeder assemblies, and more specifically, relates to feeder assemblies for a tube-filling machine. The present invention includes at least one robotic arm capable of moving tubes and tube holders between two locations. The robotic arm may also move the tubes and tube holders relative to one another in order that the distance between adjacent tubes is substantially equal to the holders which carry and house the tubes.

The invention relates to machines/lines which, starting with emptypackaging tubes, process these in the machine, including filling andsealing them, and output the tubes from the machine with highproductivity/capacity.

More precisely, the invention relates to a feeder intended to constitutea principal component in such a high-production machine.

PRIOR ART

A number of different concepts have been proposed to increase the numberof tubes produced per unit of time in a tube-filling line.

In practice, intermittently operating lines have for many years formedthe basis for tube handling. Such lines are operationally reliable andcan, within certain limits, be converted relatively easily to the actualrequirements regarding production volumes, type of sealing, tubedimension, etc.

An advantageous type of intermittently operating machine is based on theprinciple of the continuous conveyor with two straight sections.Stations for processing the tubes are arranged along one straightsection, and the other straight section is used for introducing emptytubes and in certain cases also for discharging filled tubes. The methodof working, and the control, of the working tools in the processingstations can be arranged comparatively simply along a straight path. Itis possible, for example, to freely adapt the length of the straightpath so that a number of identical stations can simultaneously executethe same type of operation on a number of tubes, for example for sealingthem. Such extension of the straight section and the provision ofmultiple stations increase the production volume.

Of course, the production volume per unit of time is also raised byincreasing the speed of advance of the conveyor. However, this cannot beincreased without restriction since the necessary time for processing indifferent stations imposes a limit. In addition, there are limits towhat the arrangement will tolerate in terms of acceleration anddeceleration.

A number of different concepts have been proposed in which, whileretaining a partly intermittent operation of a tube-handling line, ithas been attempted to increase the number of tubes produced per unit oftime.

In such a concept, a continuously operating filling station has beenchosen and this has been separated from the stations which are neededfor subsequent processing of filled tubes. A traditional, intermittentlyoperating conveyor has been used to convey the tubes to the subsequentprocessing stations once the tubes have been filled in the filler whichis independent of the conveyor.

In this combination of continuous and intermittent operation, it hasbeen proposed to use programmable robots on the one hand between themagazine for empty tubes and the filler, and on the other hand betweenthe filler and the conveyor to the processing stations.

A problem in this context is that it has not been possible to find asimple, adaptable solution to the problem of transferring the tubesbetween magazine, filler and conveyor.

Also used as transfer arrangements/feeders in connection with tubefillers, especially for transferring empty tubes from a magazine to aconveyor, are feeders which operate on the principle of collecting anumber of tubes from a magazine, placing these tubes on an arrangement,usually a conveyor, in order to separate the tubes, after which furtherarrangements are needed for turning the tubes through 90° so that these,with the correct mutual spacing, can finally be pressed down intoholders on the conveyor in the actual tube-filling machine. In terms oftheir construction, the known feeders thus remain to a large extent tiedto the machine, and there is very limited possibility of introducingsuch a feeder into an environment other than the one for which it wasconstructed.

OBJECT OF THE INVENTION

The object of the invention is to develop the robot concept intube-handling lines and to provide an arrangement for a robot whichmakes available a tube feeder of high capacity and easy adaptability tothe requirements set in terms of production volume and production linedesign.

THE INVENTION

The object of the present invention is achieved by providing a feederfor a tube-filling machine including a sequence of stations locatedalong a continuous conveyor having a plurality of tube holders. Thesequence of stations may be adapted for filling and sealing emptypacking tubes. Additionally, at least one robot device having an arm maybe provided with the assembly in order to transfer the tubes betweenvarious locations.

Advantageous developments of the invention are set out in the dependentclaims.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described in greater detail below with referenceto the attached drawings, in which:

FIG. 1 is a diagrammatic representation of the layout of a tube-handlingline with feeders according to the invention,

FIG. 2 is a diagrammatic representation, in a perspective view, of tworobots with feeders according to the invention, indicating the workingmethod by which the feeders work in the line in FIG. 1,

FIG. 3 shows the arrangement from FIG. 2 at a slightly different angle,

FIG. 4 shows in greater detail the tube-handling members on the beam inthe position for insertion, and the means used for positioning thetube-handling members, and

FIG. 5 shows the tube-handling members and the beam in position forcollecting empty tubes.

ILLUSTRATIVE EMBODIMENT

FIG. 1 shows a layout for a tube-handling machine with high productionspeed, up to 400-600 tubes per minute.

The machine has a continuous, intermittently operated conveyor 10 whichis placed in the horizontal plane and which has two straight sections 10a, 10 b and passes around deflector wheels 10 c, 10 d. Arranged alongthe conveyor there are double rows of tube holders 11, 12 (FIG. 2). Eachpair of tube holders forms a unit, and in the embodiment shown each pairlies with its centre lines in a plane at right angles to the directionof transport, and with well-defined spacing (distance between the centrelines).

In the case in question, the intermittent operation is such that theconveyor advances in steps of a length of two spacings. Assuming thatthe machine is driven at 100 cycles per minute and that all the tubeholders can be used, this gives a production capacity of 2×2×100=400tubes per minute.

In the layout shown in FIG. 1, there are double collection stations 13,14 where empty tubes are picked up directly from among tubes arranged inordered rows in transport packages 15, 16, and where the tubes arearranged with a predetermined centre distance. As soon as a transportpackage is empty, the next one is advanced to the respective collectionstation 13, 14 in the direction of the arrows 17, 18.

Empty transport packages are ejected in the direction of the arrows 19,20.

Two programmable robots 21, 22 with feeders (which will be describedlater) in the form of beam arrangements 23, 24 collect empty tubes fromthe transport packages which are located in the collection stations andinsert these tubes into the tube holders 11, 12 on the conveyor 10.

The work range of the robot 22 is shown diagrammatically by the brokenline 25, and that of the robot 21 by the line 25′.

The tubes are thus inserted into the holders 11, 12 on the straightsection 10 a of the conveyor and are advanced by the said intermittentmethod in the direction of the arrows 26, 27.

Arranged along the semicircular section 10 d of the conveyor there arestations (not shown) for tube cleaning and orientation of adornments.The tubes then arrive at a filling station 28 equipped with thenecessary number of filling nozzles for the stepped advance in question,in the present case four filling nozzles.

Between the filling station 28 and a heat activation station 29 (forpre-heating of the tube ends), there is a section with devices (notshown) for identifying and ejecting faulty tubes.

After heat activation of the tubes in the station 29, these tubes arriveat a clamping and embossing station where the tube ends are finallysealed.

This is followed by an ejection station (not shown) for faulty tubes.

Filled and approved tubes are finally delivered in the direction of thearrows 30 to a delivery station and are transported in the direction ofarrow 31 by means of a delivery conveyor.

FIG. 2 shows, in a simplified perspective view, the principle by whichthe feed robots 21, 22 work. On the arm of the robot 21 there is a beamarrangement 34 (the arrangement 23 in FIG. 1) which consists of astraight main beam 36 and two straight beam parts 37, 38 of essentiallythe same length as the main beam. The beam part 38 can be turned bymeans of a piston/cylinder arrangement (not shown) about an axis ofrotation 39 parallel to the main beam 36. Like the other beam parts, thebeam part 38 is provided with gripping devices 41 (FIG. 4) intended togrip the tubes 40 from the inside and carry these releasably on therespective beam. In FIG. 2, the beam part 38 is shown with the beam, andwith the gripping devices 41 thereon, turned approximately 90° about theaxis 39, from a position at right angles to the plane of the conveyor,which coincides with or is parallel to a plane at right angles to thevertical centre axes of the two rows of parallel tube holders.

On the beam part 38, in the same way as on the other beam parts, eachgripping device 41 is supported by a holder plate 42 which in turn issupported slidably on a guide arrangement 43 which extends in thelongitudinal direction of the beam. The holder plates are connected toeach other by a belt 44 with a certain predetermined belt length betweenadjacent holder plates.

In one end position, the extent of the holder plates in the longitudinaldirection of the guide arrangement defines a first, lesser centredistance between the gripping members or devices 41 when the holderplates are driven to a position where they bear against each other. Thisfirst lesser centre distance is chosen such that it corresponds to thecentre distance between adjacent tubes in rows of tubes in the transportpackages in the feed stations 17 and 18, respectively.

In a second end position, the belt 44 defines a second, greater centredistance between the gripping devices 41 when the belt is fullystretched between adjacent holder plates 42. This second, greater centredistance corresponds to the spacing of (centre distance between) thetube holders 11, 12 on the conveyor.

The change-over of the holder plates 42 between the said first andsecond end positions is effected with the aid of a pair ofpiston/cylinder arrangements 45, 46 in which each extended piston rodend manoeuvres one of the outer holder plates 42 in the set of holderplates on the guide arrangement 43.

The rotational movement of the beam part 38 about the axis 39 isgenerated by a further piston/cylinder arrangement (not shown).

As can be seen from FIG. 4, each gripping device 41 is divided in thelongitudinal direction in order to permit pivoting, about a diametralaxis in the base plane, of the parts which engage the inside of a tube.This pivoting of the parts of a gripping device is generated with apneumatic cylinder arrangement 47 belonging to each grip device.

The robot 22 is identical to the robot 21 and has, on its robot arm, thesame type of beam arrangement 35 as the robot 21.

In the operating stage shown in FIG. 2, the gripping devices 41 in boththe beam sections on the robot 22 are driven together to the minimumcentre spacing and the robot arm 31 is in the process of lifting tworows of tubes out of the associated transport packages 15 and 16,respectively.

At the same time, the beam part 37 of the beam arrangement 24 on therobot 21 is in the process of lowering a set of tubes into the outer rowof tube holders 12 on the conveyor.

The gripping devices 41 are here driven apart to the defined greaterspacing determined by the belt 44.

After the set of tubes on the beam part has been pressed down into theholders 12 in the outer row of holders, the conveyor is advanced insteps of a number of spacings, in the present case two, at the same timeas the beam part 38 is turned about its pivot axis 39 to a position inwhich the gripping devices 41 and the tubes 40 located thereon areoriented vertically. Thereafter, the set of tubes is pressed down intoassociated holders on the inner row of holders 11 as soon as the saidstepped advance has been completed. After this, the robot arm 32 startsits return movement to the collection station 21.

The robot arm 33 of the robot 22 gradually works its way to the tubefeed position with the holder plates 44 driven apart and with the beampart 38 turned to the position according to FIG. 2. During this periodof time, the tube holders 11, 12 have been advanced sufficiently topermit insertion of the whole set of tubes on the gripping device 41into tube holders following directly on those in which tubes havealready been inserted during the previous stage (by means of the robot21).

At start-up, manual assistance may be needed for the feed. The reasonfor this is that on the conveyor side 10 b where the processing stationsare located, there should at all times be tubes in all the tube holders,and in particular in the first ones, before processing is started up.

Although the invention has been described in connection with double rowsof tube holders, it will be appreciated that the feeder device accordingto the invention is not limited to this, and instead it can be appliedin general and by means of its basic construction can be easily modifiedto the requirements in question. The invention is thus limited only bywhat is stated in the attached patent claims.

What is claimed is:
 1. A feeder for a tube-filling machine including asequence of stations located along a continuous conveyor provided with aplurality of tube holders, the sequence of stations adapted for fillingand sealing empty packaging tubes, the continuous conveyor including astraight section adapted for handling empty packaging tubes from amagazine thereof and inserting the empty packaging tubes into the tubeholders, the tube holders having a predetermined mutual spacing on theconveyor, the feeder comprising: at least one robot device having an armcapable of rotating, said arm provided with a beam arrangement, saidbeam arrangement including at least one elongated straight beam, whereina plurality of tube-handling members are arranged on said straight beam;a positioning element for positioning each of said tube-handling membersin a first position and moving said tube-handling members into a secondposition, wherein a distance between adjacent tube-handling members insaid first position corresponds to a spacing between said plurality oftube holders on said conveyor and a distance in said second positioncorresponds to a center distance between a plurality of adjacent tubesin said magazine.
 2. The feeder according to claim 1, wherein said beamarrangement includes two elongated straight beams, said beams providedwith a set of tube-handling members, wherein at least one of said beamscan rotate about an longitudinal axis.
 3. The feeder according to claim2, wherein said tube-handling members are adapted for gripping an insideof said plurality of tubes.
 4. The feeder according to any one of claim1, 2 or 3, wherein two robots are arranged between said magazine andsaid straight beam arrangement, wherein said robots are programmed toalternatively collect said tubes from said magazine and transfer saidtubes into said tube holders.
 5. The feeder according to claim 4,wherein said conveyor includes two rows of said plurality of tubeholders, wherein said feeder has two beam parts, each with a first setand second set of tube-handling members, said first set of tube-handlingmembers being arranged to insert said tubes into said first row of saidtube holders and said second set of tube-handling members arranged toinsert tubes into a second row of said tube holders.
 6. The feederaccording to claim 1, wherein said first position and said secondposition differ in dimension.
 7. A feeder for a tube filling machine,the feeder comprising: a plurality of tube holders arranged adjacent toone another; a plurality of tubes arranged adjacent to one another; atleast one robot device having an arm capable of rotating, said armprovided with a beam arrangement, said beam arrangement including atleast one elongated straight beam, wherein a plurality of tube-handlingmembers are arranged on said straight beam; and a positioning elementfor positioning each of said tube-handling members in a first positionand moving said tube-handling members into a second position, wherein adistance between adjacent tube-handling members in said first positioncorresponds to a spacing between said plurality of tube holders and adistance in said second position corresponds to a center distancebetween said plurality of tubes.
 8. The feeder according to claim 7,wherein said beam arrangement includes two elongated straight beams,said beams provided with a set of tube-handling members, wherein atleast one of said beams can rotate about an longitudinal axis.
 9. Thefeeder according to claim 7, wherein said tube-handling members areadapted for gripping an inside of said plurality of tubes.
 10. Thefeeder according to any one of claim 7, 8 or 9, further comprising amagazine and a conveyor, wherein two robots are arranged between saidmagazine and said straight beam arrangement, wherein said robots areprogrammed to alternatively collect said tubes from said magazine andtransfer said tubes into said tube holders.
 11. The feeder according toclaim 10, wherein said conveyor includes two rows of said plurality oftube holders, wherein said feeder has two beam parts, each with a firstset and second set of tube-handling members, said first set oftube-handling members being arranged to insert said tubes into saidfirst row of said tube holders and said second set of tube-handlingmembers arranged to insert tubes into a second row of said tube holders.12. The feeder according to claim 7, wherein said first position andsaid second position differ in dimension.
 13. A feeder for a tubefilling machine, said feeder comprising: a plurality of tube holders; aplurality of tubes; at least one robot device having an arm, said armprovided with a beam arrangement having a longitudinal axis, said beamarrangement including at least two elongated straight beams, wherein atleast one of said straight beams includes a set of tube-handling membersarranged on said beam, wherein at least one of said beams can rotateabout said longitudinal axis; and a positioning element for positioningeach of said tube-handling members in a first position and moving saidtube-handling members into a second position, wherein a distance betweensaid tube-handling members in said first position corresponds to aspacing between said plurality of tube holders and a distance in saidsecond position corresponds to a center distance between said pluralityof tubes.
 14. The feeder according to claim 13, wherein saidtube-handling members are adapted for gripping an inside of saidplurality of tubes.
 15. The feeder according to any one of claim 13 or14, further comprising a magazine and a conveyor, wherein two robots arearranged between said magazine and said straight beam arrangement,wherein said robots are programmed to alternatively collect said tubesfrom said magazine and transfer said tubes into said tube holders. 16.The feeder according to claim 15, wherein said conveyor includes tworows of said tube holders, wherein said feeder has two beam parts, eachwith a first set and second set of tube-handling members, said first setof tube-handling members being arranged to insert said tubes into saidfirst row of said tube holders and said second set of tube-handlingmembers arranged to insert tubes into said second row of said tubeholders.
 17. The feeder according to claim 13, wherein said firstposition and said second position differ in dimension.